Constitutive expression of the human fibroblast interferon gene is elicited in cultured mouse L cells by the long terminal repeat of Moloney sarcoma virus

Abstract

We have used a chimerical plasmid containing the long terminal repeat of Moloney sarcoma virus to direct the expression of the human fibroblast interferon gene in mouse L cells. Constitutive secretion in cell culture supernatants was achieved at a level higher than 2.103 U/ml/72 h. The antiviral activity was indistinguishable from that of authentic human fibroblast interfereon by both immunological and physical criteria. Northern blotting analysis showed unambiguously that the expression was under the control of the putative transcriptional regulatory sequences previously described in the long terminal repeat of Moloney murine sarcoma virus (Dhar et al. 1980).